Moving from SQL Anywhere to PostGres - First Time

Hello,

We have 700 user install base using Sybase SQL Anywhere 9.02

We are looking at migrating these installations over to PostGres

1.  Very Very Short Answer Please - why should we?

2.  Does anyone have a utility or migration application to read SQL Anywhere 
to go to PostGres

3.  Does PostGres handle column descriptions (ie: you can give each column a 
50 character description) and then access it via SQL Result Set (like I can 
do in Sybase)

4.  Is there any Date/TimeStamp issues and conversions I need to know about. 
I use simply a DATE field and a TIME field - but do not use DATE/TIME stamp 
fields together.

5.  What UI/Developer tools (GUI) are available to manage the database as 
well as add/change columns rather than doing it via SQL commands.

Thank  you.

-Robert